Recent progress in all-perovskite tandem solar cells and modules: redefining limits

All-perovskite tandem solar cells (APTSCs) are garnering considerable attention as efficiencies of single-junction solar cells approach the Shockley–Queisser limit. The operation of APTSCs relies on the coordinated performance of the top and bottom cells, which together offer an optimal balance between cost-effectiveness and power output. Despite their promising architecture, the performance of APTSCs remains constrained by several intrinsic and extrinsic factors such as grain boundaries, bulk and interfacial defects, along with crystallization challenges. Nonetheless, the implementation of mitigation strategies enables effective resolution of these challenges, thereby enhancing the adaptability and performance potential of APTSCs. This review systematically examines the individual components, besides whole architectures of 2T and 4T of APTSCs, along with their recent advancements. It highlights a range of performance enhancement strategies, including the optimization of interconnecting layers, the integration of light-trapping mechanisms, and the incorporation of quasi-2D perovskites. The discussion further extends to the fabrication of large-area devices, a critical step toward commercial scalability. Finally, the review outlines current challenges and proposes future research directions aimed at improving efficiency, stability, and manufacturability. This review outlines a comprehensive roadmap integrating innovative design strategies, advanced simulation methodologies—including finite element method and density functional theory—and state-of-the-art characterization techniques to accelerate the development of next-generation, high-performance all-perovskite tandem solar cells.